1. Field of the Invention
The present invention relates to 4-(2,2,3-trimethylcyclopent-3-en-1-yl)-but-3-en-1-ols, to their method of production, and to their use as odorants.
2. Description of the Prior Art
Derivatives of campholene aldehyde (1), a product of rearrangement of .alpha.-pinene epoxide are known as aroma chemicals of the sandalwood type (Survey: E.-J. Brunke and E. Klein, in: Fragrance Chemistry, ed. E. Theimer, Academic Press, New York, N.Y. 1982, pp. 424-26). For instance, the .alpha.,.beta.-unsaturated aldehydes obtained by aldol condensation of camphene aldehyde (1) with acetone, propionic or butyraldehyde (catalyzed by alkali hydroxides or alcoholates), and the .alpha.,.beta.-unsaturated alcohols 2, 3 and 4, obtained from the above by subsequent reduction have already been described in DE-A1 No. 992 391 as aroma chemicals with sandalwood and musk notes. ##STR2##
U.S. Pat. No. 4,052,341 describes the aldol condensation of camphene aldehyde (1) with methyl ketone (catalyzed by alkali hydroxides) to the .alpha.,.beta.-unsaturated carbonyl compounds and their subsequent reduction to a mixture of the unsaturated secondary alcohols 5/6 and the saturated alcohols 7/8.
In U.S. Pat. No. 4,173,585, the aldol condensation of camphene aldehyde with various ketones using zinc acetate dihydrate is described. In contrast to the aldol condensations catalyzed with alkali hydroxides or alcoholates, it is not the uniform .alpha.,.beta.-unsaturated ketones that are produced in this patent but rather mixtures of .alpha.,.beta.- and .beta.,.gamma.-unsaturated ketones, which are present as (Z) and (E) isomers (9-12). ##STR3##
These mixtures are said to have fragrance notes of the ionone type (sweet, woody, green, melon-like, apricot-like, flowery, violet-like, ambrigris-like). The alcohol mixtures 14-16 obtained from the mixtures of the .alpha.,.beta.- and .beta.,.gamma.-unsaturated ketones by reduction are said to possess sandalwood, cedarwood, resiny and flowery notes. The individual isomers were not isolated. Nothing is known about the odorous properties of the individual isomers.